/Engine/Plugins/Online/OnlineSubsystem/Source/Public/OnlineNotificationHandler.h
Add a notification binding for a type
[FDelegateHandle](API\Runtime\Core\Delegates\FDelegateHandle) AddPlayerNotificationBinding_Handle ( const [FUniqueNetId](API\Runtime\CoreOnline\Online\FUniqueNetId) & PlayerId, [FString](API\Runtime\Core\Containers\FString) NotificationType, const [FOnlineNotificationBinding](API\Plugins\OnlineSubsystem\FOnlineNotificationBinding) & NewBinding )